Ventilatory and arousal patterns during sleep in normal young and elderly subjects

Area of Science:

• Sleep Medicine
• Respiratory Physiology
• Gerontology

Background:

• Reduced chemosensitivity in the elderly may alter ventilation patterns during sleep.
• Previous research suggests potential age-related differences in respiratory control.

Purpose of the Study:

• To investigate age-related changes in ventilation during different sleep states.
• To compare ventilation variability and apnea occurrence between young and elderly adults.

Main Methods:

• Respiratory inductive plethysmography was used to measure ventilation in healthy young and elderly subjects.
• Ventilation was assessed across various sleep stages (awake, stage 1-2, stage 3-4).
• Apnea frequency and sleep apnea syndrome criteria were evaluated.

Main Results:

• No significant differences in mean ventilation or variability were found between age groups within specific sleep states.
• Both groups exhibited increased ventilation variability in stage 1-2 sleep, attributed to periodic breathing.
• Elderly subjects had a higher incidence of apneas, with 5 out of 13 meeting sleep apnea syndrome criteria compared to 1 out of 12 young subjects.
• Apneas predominantly occurred in stage 1-2 sleep and often terminated with electroencephalogram arousals.

Conclusions:

• While ventilation itself is not significantly different between young and elderly during sleep states, the elderly exhibit a higher propensity for apneas.
• Periodic breathing in stage 1-2 sleep may be exaggerated in the elderly, potentially leading to sleep apnea.
• These findings highlight increased sleep apnea risk in the elderly, warranting further investigation into respiratory control mechanisms.